Gas scrubber



F. G. LOVE GAS SCRUBBER May 8, 1951 2 Sheets-Sheet 1 Filed Aug. 18, 1950INVENTOR.

A 7'7'O/F/VfY Fred 6. Love F. G. LOVE GAS SCRUBBER May 8, B951 2Sheets-Sheet 2 Filed Aug. 18, 1950 F red 6. L 0 ve INVENTOR.

ATTORNEY Patented May 8, 1951 GAS SCRUBBER Fred G. Love, Houston, Texassignor to Packaged Gas Equipment Corporation, Houston, Tex., a

corporation of Texas Application August 18, 1950, Serial No. 180,151

6 Claims.

This invention relates to gas scrubbers and particularly to scrubbers ofthe type in which a stream of gas, such as natural gas, is intimatelycontacted with a suitable scrubbing liquid, such as a hydrocarbon oil,for the purpose of removing entrained detritus, such as dirt, linescale, water and other foreign matter.

Gas scrubbers of the type mentioned are conventionally installed atintervals along natural gas pipe lines in order that the gas may becleaned of the entrained foreign matter before proceeding along the nextinterval of its journey through the pipe line. The gas is normallycontacted with a suitable scrubbing liquid contained in the scrubber,and while this treatment is ordinarily very efiicient in effectingremoval of the entrained matter from the gas, some of the scrubbingliquid will, in turn, become entrained in the gas and unless removed,will be carried out of the scrubber by the gas stream, resulting both inloss of the scrubbing liquid and various other Well-known undesirableresults arising from the presence of the scrubbing liquid in the gasstream. The large volume and relatively high pressures of the gas in theusual gas pipe line greatly aggravates the carry-over conditions.Conventional scrubbers provide various knock-back, mist-extraction, orother well known devices to obviate this condition but these are oftenrelatively inefficient and may produce extensive and undesirablepressure drops in the gas stream.

Accordingly, a primary object of this invention is to provide a gasscrubber which is adapted to handle large volumes of gas at highpressures with minimum loss of pressure; which provides effectivescrubbing contact of the gas with a scrubbing liquid; and which provideshighly efficient extraction of entrained scrubbing liquid from the gas.

An important object is the provision of a scrubbing vessel having agas-liquid scrubber section and a plurality of gas-liquid separatorsections in which improved flow-directing and baflling devices arearranged in the path of the scrubbed gas to effectively remove entrainedscrubbing liquid with minimum pressure drop.

Other and more specific objects and advantages of this invention willbecome readily apparent from the following detailed description whenread in conjunction with the accompanying drawings which illustrate oneuseful embodiment in accordance with this invention.

In the drawings:

Fig. 1 is a longitudinal sectional view of a gas scrubber in accordancewith one embodiment of this invention;

Fig. 2 is a cross-sectional view along line 2-2 of Fig. 1;

Fig. 3 is a cross-sectional view along line 3-4 of Fig. 1;

Fig. 4 is a cross-sectional view along line 4- of Fig. 1;

Fig. 5 is a longitudinal partly sectional view of one element of thescrubber structure; and

Fig. 6 is a cross-sectional view along line {5-8 of Fig. 5.

Referring to the drawings, the scrubber comprises an elongated tubularshell ill, adapted to be vertically disposed, constructed of metalhaving a Wall thickness sufiicient to withstand the internal pressuresto which it may be subjected in operation. The lower end of shell Hi isclosed by a dished head Illa and the upper end is provided with a headlilb having a gas discharge connection I I communicating with theinterior of the shell at its upper end. A gas inlet connection l2communicates with the interior of shell I!) through the side thereof ata suitable point, generally about one-third the length of the shellabove the bottom. A partition plate 13 extends transversely across theinterior of the shell just above inlet connection E3. The portion of theshell below partition plate is may be generally termed the contactorsection, and is designated generally by the letter C. A relatively largediameter tubular chimney H! extends downwardly through plate It to anintermediate point in the contactor section and provides communicationbetween the sections of the shell on opposite sides of plate 53. Thelower edge of chimney I i may be provided with serrations E5 of anysuitable form. A baffle plate I 5, having a large number of generallyuniformly spaced perforations lfia therein (see Fig. 4), is arrangedtransversely of shell 10 below the lower end of chimney I 4. Aconventional gauge glass I! is arranged on the outside of the shellopposite the contactor section to indicate the level of a body ofscrubbing liquid to be maintained therein. A pipe !8 for introductionand removal of scrubbing liquid extends through chimney M from a pointadjacent the lower end of the shell and communicates with the exteriorof the shell through a nozzle is located just above partition plate l3.The inner end of inlet connection I2 is connected to an inlet nozzle 29which communicates with the annular space between the shell and theexterior of chimney I l. The upper wall of the nozzle is formed bypartition plate l3 and the lower wall is formed by an arcuate plate 28awhich extends for a short distance on opposite sides of the axis ofinlet connection E2. The side walls of the nozzle will, of cour e, beformed b the concentric walls of shell lo and chimney i=3. Thisarrangement serves to part a downward swirling movement to gasdischarging from the nozzle, as indicated by the arrows in Fig. i, thegas flowing in opposite directions about chimney i i. 10

A pair of longitudinally spaced partiti: 1 plates 2! and 22 are arrangedin an intermediate por tion of shell :9 above plate i3 and enclosebetween them a section, designated generally by ietter S1, which istermed the mary separator 1 section. An additional partition plate 23eX- tends across the shell a substantial distance abore plate 22 andnear the upper end of shell 59 the section enclosed between plates 22and 2?; lo termed the secondary separator sectio and is designatedgenerally by the letter A short centrifugal nozzle inc; ed plate ii toprovide communication between portion of the shell below plate 2 I andthe interior of primary separator section S1. The c of nozzle 2% isclosed by means of a d e 25, and the periphery of nozzle 24 is formed byplurality of vertically extending, rad

charge of gas from the nozzle and to I centrifugal component to the gasflow? nozzle 26 into the interior of priinar" section S1. (Figs. 1 and3.)

An upwardly tapering generally coni- 21 is set over nozzle 2 in co-aXialg; therewith. The base of the hood is see-ed C plate El and its diameteris made than that of the interior of the shell and s ti by annularlyspaced therefrom, formal. erally annular space 23 within primary sectionSi between the exterior of the the surrounding portion of shell Theupper end of hood 2'! is open and communicates throi plate 22 with theinterior of secondary separator section S2. A helical baffle 29 ismounted on the inner wall of hood 2'! and extends from its apex to itsbase. Bafiie 2G is conveniently constr oted of angle iron having theedge of one welded or otherwise fixedly attached to the inne Wall of thehood and the other flange in depe sition and spaced inwardly from thehood, substantially as shown. A downcom-er communicates with theinterior of hood through plate 2! and extends downwardthrough shell Iiito a point in contactor 0 near its lower end. A second downcccommunicates through plate 2! with the 28 and also extends downwardlythrough the si ell to a point in contactor section C near end.

A plurality of angularly spaced tubu adapted to provide communication linterior of secondary separator section 52 and. 55 space 28. The lowerends of nozzles duced in diameter to provide openings parativelyrestricted area communnspace 28. Tubular risers of than nozzles 32 arearranged co-as ily with and have their lower ends extend 4 tion with thespace above plate 222. A plurality of helical vanes are arranged in theannular spaces between the lower ends of risers 34 and the surroundingwalls of nozzles 32 (see Figs. 5 and 6) 23 to collect any liquid whichof plate A downcomcr 38 bottom of well 35 and exiough shell in into thelower tor section C. A manhead 35, of form is provided at one side ofaccess to the interior thereof.

ove-described operates in the l g manner: A quantitj of a suitablescrubbing liquid L will first be introduced into contactor section Cthrough pipe 18, via nozzle 19, in an amount to attain a level V suchthat the lower end of chimney Hi, ii eluding serrations [5, will besubmerged within the liquid. The open lower ends of dou-ncomers 3i and33 will likewise be may deposit on top is connected into tendsdownwardly portion of contac any convention i shell i3 to permitcomponent to the gas stream tending to throw out some or bl e detrituscarried by the gas. The pressure of the will normally be relatively h''hrough the scrubber at relati The gas than contacts the scrubbing andis forced to pass theret roug'; to reach chimney i i. In passing intochimney 5:! no gas must pass through se :ations E5 which, by reason oftheir form and arrangement, provide a relatively large amount of surfacefor effecting efficient scrubbing contact of the gas by the scrubbingliquid. Perforated baiile plate i6 serves as an additional contactormeans and prevents: the formation of eddy pockets in the surface of theliquid due to the whirling action and velocity of the gas. The path offlow of the gas through the contactor section is indicated generally bythe arrows appearing in Fig. 1. This liquid-gas contact will serve toeffec iyely scrub the gas and remove substantially all of the foreignmatter, including any water droplets carried thereby. This foreignmatter will be deposited in the body of the liquid L and when the latterhas bee inc suiiiciently dirty, it may be with dra through pipe l8 andreplaced by fresh scrubbin; liquid. Any water so-removed from the gascollect in the lower portion of the Will contactor section and may alsobe removed from time to time through pipe i3. It will be understood.that various conventional means may be employed i0 removal andreplacement of the scrubbing liquid and to maintain the desired levelthereof in the contactor section. This may accomplished continuously orintermittently in any wei known manner.

al hough now substantially free of ed fo eign matter will, as a of thedescribed contact with the scrubssarily absorb and entrain subntlties ofthe scrubbing liquid which red to obviate the undesirable res earlie Thegas carrying scrubwe upwardly and out of contactor rough chimney itoward primary ec on The gas will enter the latthrough nozzle 2:; andwill be 'gas and the numerous changes discharged radially therefrombeneath hood 2?. Vanes 26 will cause the gas to discharge generallytangentially along the inner surface of hood 2'! and with a substantialcentrifugal component which tends to throw out the particles ofscrubbing liquid carried by the gas. The gas will flow upwardly in ahelical path along the inner wall of hood 2'! where it will repeatedlycontact the several successive convolutions of helical baflle 29, thegas following the generally upward swirling path indicated by thearrows. The pitch of helical baflie 29 is preferably made opposite thatof the path of flow of the gas to increase the baflling effect. Thecontact of the gas with the baffle and the centrifugal force imparted tothe stream will knock-out or separate the major portion of the containedliquid from the gas, the particles of separated liquid depositing on thesurfaces of the baille and inner wall of the hood and drainingdownwardly along these surfaces to the top of plate 2| whence, theliquid so-sepa rated will flow through downcoiner 3?} back into the bodyof liquid L in contactor section C.

The gas leaving hood 2'! and carrying a now substantially reducedquantity of scrubbing liquid will enter secondary separator section 532wherein the gas is again forced to change direction and caused to flowdownwardly into nozzles 32 through the annular space between the nozzlesand the lower ends of risers 3 1 order to enter the open lower ends ofrisers 34. Vanes 35 again impart a swirling motion to the gas flowingtherethrough before passing into the lower ends of risers 3 3, the gasbeing preferentially directed into the risers by reason of the greaterrestriction provided by restricted openings 33. The centrifugal forceimparted to the gas at this point and the necessary changes in.direction cause separation of additional quantities of liquid from thegas and this liquid will drain through the openings 33 and will fall onplate 2! outside hood 2'2 whence the separated liquid will drain throughdowncomer 35 back into the main body of liquid L in the contactorsection. The repeated whirling movements imparted to the in directionthereof in passage through the primary and secondary separator sectionswill normally be sufficient to remove all but insignificant traces ofliquid from the gas, so that the gas leaving secondary separator S2through the upper ends of risers 34 will be sufficiently clean and freeof scrubbing liquid that it may be conducted directly to the scrubberdischarge connection Ii. Any additional liquid which may separate fromthe gas leaving the upper ends of risers 3 3 will fall on the top of theplate 23 and collect in well 36 whence it will flow through downcomer 33back into the body of liquid L in contactor section C.

By means of the above-described scrubber, highly efiicient scrubbing ofgas may be accomplished with minimum loss of scrubbing liquid. Thedescribed scrubber operates with a relatively small pressure drop andhas capacity for scrubbing exceptionally large volumes of gas.

It will be understood that various alterations and changes may be madein the details of the illustrative embodiment within the scope of theappended claims but without departing from the spirit of this invention.

What I claim and desire to secure by Letters Patent is:

1.. A gas scrubber, comprising, a vertically disposed tubular vesselhaving a partition across its 6. lower portion, means for introducinggas into said lower portion into intimate scrubbing contact with a bodyof a scrubbing liquid maintained therein, a conduit for dischargingscrubbed gas from said lower portion to the upper portion of saidvessel, and separator means for separating from said gas scrubbingliquid introduced therein by said scrubbing contact, said separatormeans comprising primary and secondary separator sections arranged insaid vessel at successively higher elevations above said partition, anozzle having a tangential discharge for introducing the scrubbed gasinto the lower portion of said primary separator section, an upwardlytapering generaliy conical hood having its base surrounding said nozzleand communicating at its upper end with said secondary separatorsection, a helical baiile mounted on the, inner wall of said hood, aplurality of flow-reversing discharge nozzles for discharging the gasfrom said secondary separator section to the upper portion of saidvessel, means for discharging separated gas from the upper portion ofsaid vessel, and means for returning scrubbing liquid separated in saidseparator sections to said body of scrubbing liquid.

2. A gas scrubber according to claim 1, where in each of saidflow-reversing discharge nozzles comprises, a verticall disposed tubularouter member having a flow restriction in its lower end, and a tubularinner member having its lower end concentrically extendinginto the upperportion of the bore of said outer member and having its upper endcommunicating with the portion of said vessel above said secondaryseparator section.

3. A gas scrubber according to claim 1, wherein each of saidflow-reversing discharge nozzles comprises, a vertically disposedtubular outer member having a flow restriction in its lower end, atubular inner member having its lower end concentrically extending intothe upper portion of the bore of said outer member and having its upperend communicating with the portion of said vessel above said secondaryseparator section, and deflector means arranged in the annular spacebetween said inner and outer tubular members to impart a centrifugalcomponent to the gas passing downwardly through said annular space.

4. A gas scrubber, comprising, a vertically disposed tubular vessel, aseries of longitudinally spaced partitions extending across the interiorof said vessel to divide the same into a contactor section and primaryand secondary separator sections at successively higher elevations insaid vessel, means for introducing gas into said contactor section intointimate scrubbing contact with a body of a scrubbing liquid maintainedin said contactor section, a conduit for discharging scrubbed gas fromsaid contactor section toward said primary separator section, anupwardly tapering generally conical conduit extending through saidprimary separator section into communication with said secondaryseparator section, means for introducing the scrubbed gas tangentiallyinto the lower portion of said conical conduit, bafile means mounted onthe inner wall of said conical conduit for effecting a plurality ofbaflling contacts with the scrubbed gas passing therethrough to saidsecondar separator section, means arranged in said secondary separatorsection for imparting a plurality of direction changes to the gaspassing therethrough, means for dischargin the gas from said secondaryseparator means into the upper portion of said vessel, means fordischarging gas from said upper portion of said vessel, and means forreturning scrubbing liquid separated from said gas in said separatorsections to said body of liquid in said contactor section.

5. A gas scrubber, comprising, a vertically disposed tubular vessel, aseries of longitudinally spaced partitions extending across the interiorof said vessel to divide the same into a contactor section and primaryand secondary separator sec tions at successively higher elevations insaid vessel, means for admitting gas into said contactor section intointimate scrubbing contact with a body of a scrubbing liquid maintainedin said contactor section, a conduit for discharging scrubbed gas fromsaid contactor section toward said primary separator section, an inletnozzle for admitting said scrubbed gas into the lower end of saidprimary separator section, said nozzle having a tangential discharge, anupwardly tapering generally conical hood having its base surroundingsaid nozzle and communicating at its upper end with said secondaryseparator section, a helical baffle mounted on the inner wall of saidhood, a plurality of discharge nozzles for discharging the scrubbed gasfrom said secondary separator section to the upper portion of saidvessel, means arranged in said discharge nozzles to impart a pluralityof direction changes to the gas passing therethrough, means fordischargin the gas from the upper portion of said vessel, and means forreturning scrubbing liquid separated from said gas in said separatorsections to said body of liquid in said contactor section.

6. A gas scrubber, comprising, a verticall disposed tubular vessel, aseries of longitudinally spaced partitions extending across the interiorof said vessel to divide the same into a contactor section and primaryand secondary separator sections at successivel higher elevations insaid vessel, said contactor section having a body of a scrubbing liquidmaintained therein, a conduit for discharging scrubbed gas from theupper por tion of said contactor section and having its lower endsubmerged beneath the surface of said body of liquid, means forintroducing gas into said contactor section along a tangential pathabove said body of liquid and between the exterior of said conduit andthe surrounding wall of said vessel, means carried by the submerged endof said conduit to effect intimate contact between said body of liquidand said gas in its passage to the interior of said conduit, an upwardlytaperin generally conical conduit extending through said primaryseparator section into communication with said secondary separatorsection, means for introducing the scrubbed gas tangentially into thelower portion of said conical conduit, baffle means mounted on the innerwall of said conical conduit for effecting a plurality of bafiiingcontacts with the scrubbed gas passing therethrough to said secondaryseparator section, means arranged in said secondary separator sectionfor imparting a plurality of direction changes to the gas passingtherethrough, means for discharging the gas from said secondaryseparator section into the upper portion of said vessel, means for.discharging gas from said upper portion of said vessel, and means forreturnin scrubbing liquid separated from said gas in said separatorsections to said body of liquid in said contactor section. FRED G. LOVE.

REFERENCES CITED following references are of record in the file of thispatent:

UNITED STATES PATENTS Number Name Date 1,920,437 Sillers Aug. 1, 19332,087,219 Dorfan July 13, 1937 2,102,705 Henderson et al. Dec. 21, 19372,354,677 Fisher Aug. 1, 1944

